A product under the trade name NEEDLE-PRO® has been sold by the assignee of the instant invention for a number of years. The NEEDLE-PRO® product is described in U.S. Pat. No. 5,154,285, among other patents assigned to the instant assignee. Briefly, NEEDLE-PRO® is a safety needle device that has a vacuum tube holder having a needle protection housing pivotable relative to the tube holder. In particular, the needle protection housing is hingedly attached to a collar or base, which is mounted about a neck or a receptacle end of the vacuum tube holder. As described in the '285 patent, the being sold NEEDLE-PRO® product has a circumferential protuberance, or boss, formed at the receptacle end, or neck, of the holder. A counterpart circumferential groove is formed about the inner wall of the base, so that when the base is fitted onto the receptacle end of the holder, the boss is mated to the groove so that the base is rotatable about the receptacle end. The neck, or receptacle end, of the holder has a channel or aperture that is internally threaded so that a conventional double-ended needle assembly is able to be threadedly mated thereto by means of its externally threaded needle hub. The disclosures of U.S. Pat. No. 5,154,285 and U.S. Pat. No. 5,277,311, a CIP of the '285 patent, are incorporated by reference to the disclosure of the instant application.
With the protuberance/groove configuration, the needle housing is able to be rotated about the receptacle end of the holder. So that the housing may be stopped at the desired orientation relative to the holder, the respective dimensions of the internal groove of the base and the circumferential boss at the neck are such that a given friction is provided, so that theoretically the rotation of the housing relative to the receptacle end of the holder may be controlled.
During the many years of use of the NEEDLE-PRO® product, there have been instances where the housing freely rotates about the receptacle end of the housing, and also where the friction between the base and the receptacle end is such that the base seizes to the neck when the housing is turned relative to the holder. These problems most likely result from the dimensional variances of the molded plastic base and receptacle end of the holder. In other words, if both the base and the receptacle end to which the base is to be mounted were manufactured to have the desired allowable dimensional tolerances, the assembled product would most likely have a base that may rotate in an acceptable fashion about the receptacle end. But if either or both of the base and the receptacle end to which the base is to be fitted was/were molded with their dimensions outside their respective allowable tolerances, then the base and the receptacle end may either lock up, when the housing is rotated relative to the holder, or rotate loosely.